Infinitive (imperfective): знать — "to know (a fact, a person, a language) — a steady state" Infinitive (perfective): узна́ть — "to find out, to come to know; to recognize" Type: a prefixed pair where the prefix у- shifts the meaning, not merely the aspect
знать looks like an easy beginner verb — and its present tense is — but its perfective partner hides a subtle lesson about how Russian aspect works. знать describes a state: knowing a fact, knowing a person, knowing a language. A state has no natural endpoint, so it is inherently imperfective; you cannot "complete" knowing. The perfective узна́ть therefore does not mean "to finish knowing" — it cannot. Instead it names the moment you enter the state: "to find out, to come to know." From that same "moment of recognition" sense comes its second meaning, "to recognize" — Я тебя́ не узна́л ("I didn't recognize you"). Understanding why узна́ть isn't just "the perfective of know" is the key to this page, and a window into how Russian prefixes reshape meaning, covered on the perfective prefixes and meaning page.
Present tense (знать, imperfective) — first conjugation, fully regular
Only the imperfective знать has a present. It is a model first-conjugation verb: take the stem зна-, add -ю, -ешь, -ет, -ем, -ете, -ют, and keep the stress on the stem throughout. The perfective узна́ть has no present — the узна́ю column below is its future.
| Person | знать — PRESENT | узна́ть — FUTURE (perfective) |
|---|---|---|
| я | зна́ю | узна́ю |
| ты | зна́ешь | узна́ешь |
| он / она́ / оно́ | зна́ет | узна́ет |
| мы | зна́ем | узна́ем |
| вы | зна́ете | узна́ете |
| они́ | зна́ют | узна́ют |
Note that the forms look almost identical — the prefix у- is the only difference, and the stress stays on the -на́- of узна́ть. There is a tempting false trail here: do not confuse perfective узна́ю "I'll find out" with the imperfective узнаю́ of the secondary verb узнава́ть "I'm finding out / getting to know" (узнаю́, узнаёшь). Same letters, different stress and different aspect.
Я зна́ю э́тот го́род как свои́ пять па́льцев.
I know this city like the back of my hand. — зна́ю, present state; accusative object.
Ты зна́ешь, во ско́лько начина́ется фильм?
Do you know what time the film starts? — зна́ешь + embedded question; everyday.
Они́ не зна́ют, что де́лать да́льше.
They don't know what to do next. — не зна́ют + что-clause.
Past tense
Both members build a normal, regular gender-marked past with stress on the stem (знать) or on -на́- (узна́ть). No surprises.
| Gender / number | знать (impf) | узна́ть (pf) |
|---|---|---|
| masculine | знал | узна́л |
| feminine | зна́ла | узна́ла |
| neuter | зна́ло | узна́ло |
| plural | зна́ли | узна́ли |
This is where the meaning split is sharpest. знал = "I knew (was in a state of knowing)"; узна́л = "I found out" or "I recognized" — the entry into knowing or the flash of recognition. The same form узна́л carries both English ideas, and only context tells them apart.
Я всегда́ знал, что ты спра́вишься.
I always knew you'd manage. — знал: a lasting state of knowing, imperfective.
Я узна́л об э́том то́лько вчера́.
I only found out about it yesterday. — узна́л: the moment of finding out, perfective + об + prepositional.
Я тебя́ не сра́зу узна́л — ты постри́гся!
I didn't recognize you at first — you've cut your hair! — узна́л = 'recognized', the same perfective.
Future tense
The pair splits the usual two ways, and the meanings stay distinct.
- знать (imperfective) → compound future: бу́ду знать "I'll know / I'll keep it in mind."
- узна́ть (perfective) → simple future (conjugated above): узна́ю "I'll find out."
| Person | знать → бу́ду знать | узна́ть → simple future |
|---|---|---|
| я | бу́ду знать | узна́ю |
| ты | бу́дешь знать | узна́ешь |
| он / она́ / оно́ | бу́дет знать | узна́ет |
| мы | бу́дем знать | узна́ем |
| вы | бу́дете знать | узна́ете |
| они́ | бу́дут знать | узна́ют |
The everyday "I'll find out and let you know" is the perfective узна́ю: one act of finding out. The compound бу́ду знать is closer to "now I'll know (for the future) / I'll bear it in mind."
Я узна́ю расписа́ние и напишу́ тебе́.
I'll find out the schedule and text you. — узна́ю: one future act of finding out.
Тепе́рь я бу́ду знать, к кому́ обраща́ться.
Now I'll know who to turn to. — бу́ду знать: a future state of knowing.
Imperative
The imperfective imperative знай(те) is largely confined to set phrases and reassurances ("know that…, rest assured"); the everyday command is the perfective узна́й(те) "find out!"
| Addressee | знать (impf) | узна́ть (pf) |
|---|---|---|
| ты (informal) | знай | узна́й |
| вы (formal / plural) | зна́йте | узна́йте |
Узна́й, пожа́луйста, рабо́тает ли магази́н в воскресе́нье.
Could you find out whether the shop is open on Sunday? — узна́й + ли-clause; one specific task.
Зна́йте: мы всегда́ ра́ды вам помо́чь.
Rest assured, we're always glad to help you. — set imperative зна́йте, reassurance.
Participles and verbal adverbs
| Form | знать (impf) | узна́ть (pf) |
|---|---|---|
| present active participle | зна́ющий "knowing / knowledgeable" | — (perfectives have none) |
| past active participle | зна́вший | узна́вший |
| past passive participle | — | у́знанный "recognized / found out" |
| verbal adverb | зна́я "knowing" | узна́в "having found out" |
The participle зна́ющий has come to mean "knowledgeable, competent" (зна́ющий специали́ст "an expert who knows their stuff"). The verbal adverb зна́я is common: Зна́я его́ хара́ктер, я не удиви́лся — "Knowing his character, I wasn't surprised." The perfective узна́в ("having found out") is frequent in narrative.
Узна́в но́вость, она́ сра́зу позвони́ла ма́ме.
Having heard the news, she immediately called her mum. — verbal adverb узна́в, perfective.
Key uses & collocations
1. знать / узна́ть + accusative — knowing a thing or person
The thing or person known is a direct object in the accusative: знать а́дрес, пра́вду, отве́т; знать кого́-то. With animate objects the accusative is visible (знать его́, её, тебя́). See the accusative direct object page.
Я не зна́ю её но́мер телефо́на.
I don't know her phone number. — accusative object но́мер.
2. узна́ть о / об + prepositional — finding out ABOUT something
In its "find out" sense, узна́ть often takes о/об + prepositional for the topic ("hear about, learn about"): узна́ть о реше́нии, об ава́рии. This о-construction is on the about-о page.
Мы узна́ли о пробле́ме сли́шком по́здно.
We found out about the problem too late. — узна́ть о + prepositional пробле́ме.
3. узна́ть = to recognize (по + dative for the giveaway)
In the "recognize" sense, the clue by which you recognize someone takes по + dative: узна́ть по го́лосу (recognize by voice), по похо́дке (by gait), по глаза́м (by the eyes).
Я узна́л тебя́ по го́лосу, да́же не ви́дя лица́.
I recognized you by your voice without even seeing your face. — узна́ть по + dative го́лосу.
4. знать как / что / где — knowing an embedded clause
A huge slice of everyday usage is знать + an embedded question (как, что, где, кто, когда́): знать, как э́то рабо́тает. Russian, unlike English, keeps a comma before the embedded clause.
Никто́ не зна́ет, где он сейча́с.
Nobody knows where he is now. — знать + где-clause.
Common Mistakes
❌ Вчера́ я знал э́ту но́вость. (meaning: I learned it yesterday)
Wrong verb — 'to learn / find out' a piece of news is perfective узна́ть, not знать. знал means you were already in a state of knowing.
✅ Вчера́ я узна́л э́ту но́вость.
Yesterday I found out this news.
❌ Я не знал тебя́ в но́вой причёске. (meaning: didn't recognize)
Wrong verb — 'didn't recognize' is the perfective узна́ть: 'Я не узна́л тебя́.' знать is the steady state of knowing a person.
✅ Я не узна́л тебя́ в но́вой причёске.
I didn't recognize you with your new hairstyle.
❌ За́втра я бу́ду узна́ть расписа́ние.
Aspect error — the бу́ду future needs an imperfective infinitive. The perfective узна́ть makes its own future: узна́ю (no бу́ду).
✅ За́втра я узна́ю расписа́ние.
Tomorrow I'll find out the schedule.
❌ Я узна́л об но́вости. / Я узна́л о э́том.
Preposition form — use 'об' before a vowel and 'о' before a consonant: об ава́рии but о но́вости, об э́том.
✅ Я узна́л об э́том из газе́т.
I found out about it from the papers.
Key Takeaways
- знать = a steady state ("to know"); it has no clean perfective, because you cannot "finish" knowing. Its present is a model first-conjugation set (зна́ю, зна́ешь … зна́ют).
- узна́ть is not 'perfective know' — the prefix у- shifts the meaning to 'find out / come to know' and 'recognize' (the moment of entering the state).
- Future: imperfective compound бу́ду знать (future state); perfective simple узна́ю (one act of finding out).
- Government:
- accusative for the thing/person known; о/об + prepositional for finding out about something; по + dative for the clue you recognize someone by.
- Don't confuse perfective узна́ю "I'll find out" with imperfective узнаю́ (from узнава́ть) "I'm getting to know" — same letters, different stress.
Now practice Russian
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Russian→Related Topics
- Why This Prefix? Choosing the Perfective PartnerB2 — Which prefix perfectivizes a given imperfective is a lexical property you must learn WITH the verb, like gender (писа́ть→на-, чита́ть→про-, де́лать→с-). But many prefixes do more than perfectivize — they add a 'way of action' (спо́соб де́йствия): ЗА- begins, ПО- does a bit, ПРО- does throughout (or misses), ДО- finishes, ПЕРЕ- redoes, НА-...-СЯ does to satiety, РАЗ-...-СЯ gets going, ВЗ- does suddenly. Picking the wrong prefix often makes a DIFFERENT verb (переписа́ть 'rewrite' ≠ написа́ть 'write').
- Accusative: The Direct ObjectA1 — The accusative marks the direct object — the thing a transitive verb acts on directly. Verbs like чита́ть, смотре́ть, люби́ть, ви́деть, знать all take an accusative object (чита́ть кни́гу, люби́ть му́зыку). Because Russian word order is free, the case ending — not position — tells you which noun is being acted upon, so every direct object must be marked. Object pronouns (меня́, тебя́, его́, её, нас, вас, их) are accusative too.
- Verbal Aspect: The Big PictureA2 — Aspect is the spine of the Russian verb: nearly every verb belongs to a pair — imperfective (process, repetition, general fact) and perfective (a single completed whole with a result). This page explains the pair, the consequences for the tense system (perfectives have no present), and why you must decide 'process or result?' before you even pick a tense.
- Present Tense: First ConjugationA1 — The first-conjugation present paradigm: чита́ть → чита́ю, чита́ешь, чита́ет, чита́ем, чита́ете, чита́ют, with endings on the theme vowel -е-. Covers the -ать stem class (де́лать, рабо́тать), the stressed consonant-stem variant (жить → живу́, живёшь), and the -овать/-евать contraction (рисова́ть → рису́ю).
- Prepositional for Topic (о/об 'about')A1 — о/об/обо + prepositional means 'about, concerning' — ду́мать о бу́дущем, кни́га о войне́, мечта́ть о ле́те. The preposition changes shape: о before consonants (о ма́ме), об before vowels (об Анне, об э́том), обо in fixed phrases (обо мне, обо всём). Several verbs that are transitive in English need о + prepositional in Russian.
- Думать / Подумать (to think)A2 — Complete conjugation-and-usage reference for the aspect pair ду́мать / поду́мать 'to think'. A regular first-conjugation verb that governs о + prepositional for 'think about' (ду́мать о рабо́те) and что-clauses (ду́маю, что…), with a sharp contrast between ду́мать (the ongoing process), the inceptive поду́мать ('give it some thought, reconsider'), and приду́мать ('think up, invent').